JPH05317361A - Disposable diaper - Google Patents

Abstract

PURPOSE:To provide a disposable diaper to which a waist band which effectively functions without warping when worn is reasonably and functionally attached by making lower the rigidity of an absorber portion in the expanding portion of the waist band than that of the other part of the absorber. CONSTITUTION:A disposable diaper 1 has a liquid permeable surface sheet 2 forming that side of the diaper which is in contact with the skin of a person who wears it, a liquid impermeable back sheet 3, and an absorber 4 disposed between the sheets 2, 3 to absorb excrement, with elastic members 5 disposed along the longitudinal edges of both sides in order to prevent leakage from around the legs. Elastic members 6A, 6B for increasing fitness around the waist are stretched crosswise along a back side portion 10 and a belly side portion 12 at both of the longitudinal ends of the diaper, respectively. The absorber 4 is reduced in thickness at its portions overlapping the elastic members 6A, 6B so as to reduce the weight of fibers such as pulp, thereby lowering the rigidity of the absorber 4. Therefore, expansion stress required can be secured while warping of the waist band 6 can be prevented.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to absorbent articles, particularly absorbent articles used for infants, adults or incontinent persons, such as disposable diapers. More specifically, it relates to a disposable diaper having a novel waistband construction.

[0002]

2. Description of the Related Art Conventionally, various leak-proof mechanisms related to a waistband of a disposable diaper have been proposed.
These waistband proposals can be broadly classified into the following three. Proposal regarding material of waist band JP-A-59-144601 and JP-A-60-17101
Applied to a waist band using a heat-shrinkable film found in Japanese Patent Publication No. 60-17102, etc.,
JP-A-59-228007 and 60-72548.
Japanese Patent Application Laid-Open No. 61-228077 and Japanese Patent Application Laid-Open No. 62-69803 disclose a pattern in which hot melt having elastic shrinkability is applied after coating, and other waistbands. As an elastic member to be used, an elastic member having an opening is disclosed in JP-A-56-25441, and a water-absorbing shrinkable PVA-based dry nonwoven fabric is applied to a waist band in JP-A-60-185806.

Proposal on the constitution and shape of waistbands JP-A-57-193501 and 61-23900
No. 1 discloses that a waist band cooperates with leg gathers to form a crotch seal and a waist seal, one in which the fastening tape and the waist band shown in JP-A-58-87303 are interlocked, Kai 63-1
A waist band having a three-dimensional shape / pocket structure has been proposed as disclosed in Japanese Patent No. 82402 and Japanese Patent Laid-Open No. 3-195556.

Proposal Regarding Device for Attaching Waistband Generally, the production equipment of disposable diapers is such that the longitudinal direction of the disposable diaper is the flow direction, and the extension direction of the waistband is attached in the direction perpendicular to the flow direction. There is difficulty in being asked. JP-A-62-6980
No. 3 and No. 63-317576, which utilize the reversing mechanism, those which are stretched by a wheel as disclosed in JP-A-2-13454, JP-A-60-
Proposals have been made in Japanese Patent No. 17102, in which a heat-shrinkable film is fixed and then heat-treated.

[0005]

The waistband of a disposable diaper is generally provided for the purpose of improving fit around the waist of the wearer of the disposable diaper and preventing leakage of excreted liquid from around the waist. ing. However, in the disposable diapers that are currently on the market, the function of the waistband does not work effectively. One of the causes of this is that after wearing the disposable diaper for a while, the flap part where the waistband is arranged is flipped up by the wearer's walking or exercise, and it is warped back to the back sheet side, and the excreted liquid is transmitted to the top sheet. It is probable that the wearer's clothes were wet due to oozing and leakage. Further, the warp of the waist band is inferior in appearance when the disposable diaper is worn.

In order to prevent leakage around the waist, it has been proposed to provide a waste container pocket or a three-dimensional gather. However, when there is concern about stuffiness and rash, the three-dimensional portion is preferably a breathable material such as nonwoven fabric, and these materials pose a problem of causing a decrease in productivity in terms of processability such as handling,
The reality is that it has not been adopted. Therefore, it is an object of the present invention to provide a disposable diaper to which a waist band which does not warp during wearing and which functions effectively is attached rationally and functionally.

[0007]

SUMMARY OF THE INVENTION The present invention comprises a liquid permeable top sheet, a liquid impermeable back sheet, and an absorber located between the two sheets, and a pair of tape fasteners is provided on the back. Side landing zones for attaching the tape fasteners are arranged on the back sheet on the abdomen side, leg gathers are arranged so as to be able to expand and contract around both legs, and the waist band is abdomen. In at least one of the side and the back of the disposable diaper that is arranged to be able to expand and contract around the waist, the portion of the absorber in the elastic portion of the waistband has a rigidity lower than that of the other portions of the absorber. The above object is achieved by providing a disposable diaper characterized in that Further, the present invention is, in the disposable diaper, the waist band is attached to an upper portion of the absorbent body on the back side or the abdominal side, and the absorbent body is arranged with the waist band, and the waist band expands and contracts. The above object is also achieved by providing a disposable diaper characterized by notching a portion where an action is required.

According to the disposable diaper of the present invention, the central portion in the width direction of the waist band needs to be expandable and contractable so that the disposable diaper fits the wearer's body shape. The rigidity of the specific part is lower than that of the other part, while both side parts of the waistband are fixedly supported by overlapping the high rigidity part of the absorbent body, and the waistband tries to warp. Suppress movement. Conventionally, the phenomenon of waistband warping, which has been a cause of waist leakage, is eliminated, and since both side edges of the waistband are fixed by overlapping with the absorbent body, the absorbent body can be adhered to the wearer and is disposable. The leakage prevention performance of the diaper is improved.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will now be described in detail with reference to FIGS. 1 to 5 of the accompanying drawings. In the present embodiment, a flat type disposable diaper for infants provided with a fastening means will be described as an example.

In the present embodiment shown in FIGS. 1 and 2, a liquid-permeable topsheet 2, a liquid-impermeable backsheet 3, and an absorber 4 located between the two sheets are provided. The tape fasteners 7 and 7 are arranged at both side edges on the back side, and the landing zones 8 and 8 for attaching the tape fasteners 7 and 7 are arranged on the back sheet 3 on the abdominal side. The structure in which the waistband 6 is arranged to be stretchable around both legs and the waistband 6 is arranged to be stretchable around at least one of the ventral side and the back side is similar to that of the conventional disposable diaper. Then, the portion 1 of the absorbent body 4 in which the stretchable portion of the waist band 6 is located.
3A or 13B has a lower rigidity than the other parts of the absorber 4.

First, the present embodiment will be further described with reference to FIG.
(A) is a first embodiment of the present invention. The top view which looked at all the elastic elements of the disposable diaper 1 seen from the surface sheet 2 side is shown, and the top view seen from the back sheet 3 side of the disposable diaper 1 shown in FIG. 1- (a) is shown in FIG. .. The disposable diaper 1 according to the present embodiment is formed in an hourglass shape in which a central portion in the longitudinal direction (vertical direction in the drawing) is constricted, and a crotch portion 11 is formed in the constricted portion.
In the wide portion of the hourglass type in which the fastening tapes 7 and 7 are arranged, the back side portion 10 located on the back side of the wearer is formed, and the landing zones 8 and 8 corresponding to the fastening tapes 7 and 7 are arranged. A ventral side portion 12 located on the ventral side of the wearer is formed in the other wide portion.

The disposable diaper 1 generally has a liquid-permeable topsheet 2 that forms the side that contacts the wearer's skin, and a liquid-impermeable backsheet 3 provided corresponding to the topsheet 2.
And an absorbent body 4 arranged between these sheets to absorb excrement. In the disposable diaper 1 of the present embodiment, a pair of elastic members 5 and 5 are arranged along both side edges in the longitudinal direction for the purpose of preventing leakage from around the legs. Elastic members 5, 5
Is composed of two flat rubbers each, and is arranged in a curved shape that matches the shape of the crotch portion of the wearer to form a leg gather with improved fit.

Elastic members 6A and 6B are provided on the dorsal side portion 10 and the abdominal side portion 12 at both ends in the longitudinal direction in order to improve the fit around the waist. The waist bands 6 and 6 are stretched. In the example shown, the elastic members 6A, 6B
Is composed of three rubber threads. While the fastening tapes 7, 7 are arranged in the direction in which the expansion / contraction stress of the elastic member 6A for the waistband on the back side acts,
The landing tapes 8 and 8 that form landing zones are formed in the direction in which the expansion and contraction stress of the elastic member 6B on the abdominal side acts.
Are arranged in a state of being divided in the width direction. Therefore, when the diaper is worn on the wearer, the fastening tapes 7, 7
Although the landing tapes 8 and 8 are fixed in a non-stretchable state, the elastic members 6A and 6B of the waist band are stretchable in the same ring shape, so that the waist band 6 of the disposable diaper 1 is suitable for the wearer. It will fit.
As shown in FIG. 2, particularly preferably, the ends of the elastic members 5, 5 for leg gathers are connected to the elastic member 6 for waist band.
The pockets surrounded by the elastic members are formed by intersecting with A and 6B (intersection 9 in FIG. 2), and preferably by arranging them so that the stretching stresses of both interact with each other. By applying the pockets surrounded by the four sides to the excretion point of the wearer in this way, an excellent leak prevention effect is expected. Further, also in the case of disposing a gather flap having a three-dimensional shape, it is preferable that the gather flaps are arranged so as to form pocket portions that are elasticized in all directions.

In the disposable diaper 1 according to this embodiment, the elastic members 6A and 6B for the waist band are arranged so as to overlap the absorbent body 4. 1- (b) and 1- (c) show the cross-sectional shape of the absorbent body 4 in the portion overlapping with the elastic members 6A and 6B.
As shown in, the rigidity of the absorber is lowered by reducing the thickness of the absorber 4 and suppressing the basis weight of fibers such as pulp. FIG. 1- (b) and FIG. 1- (c) respectively show the XX line sectional view and the YY line sectional view of the disposable diaper 1 shown in FIG. 1- (a). In the absorber 4, the basis weight of the portions 13A and 13B in which the elastic members 6A and 6B are arranged is suppressed. in this way,
By suppressing the rigidity of the absorber 4, the required expansion / contraction stress is secured and the waist band 6 is prevented from warping. The rigidity of the low basis weight portions 13A and 13B is 10 g · cm or less, preferably 7 g · cm or less,
It is particularly preferably set to 3 g · cm or less. These stiffnesses are measured by a Taber stiffness tester. In this embodiment, a low basis weight is used as a means for obtaining low rigidity, but the means is not limited to this. Further, it is desirable that the portion of the absorbent body 4 where the landing zone 8 overlaps has a higher rigidity than other portions.

According to the present embodiment, when the elastic members 6A and 6B are formed of thread-shaped elastic bodies (thread rubber or flat rubber), the waistband portion has a weak elasticity and the hourglass-shaped absorber 4 is weak. It is supported by the rigidity of the so-called wing part, and the easiness of hitting is improved. The positions where the elastic members 6A and 6B are arranged are
There is no particular limitation, and it may be the upper surface of the topsheet 2. Further, it is preferable that the elastic members 6A and 6B are in a non-stretched state in the portions other than the low basis weight portions 13A and 13B that overlap the absorber 4. The material of the elastic members 6A and 6B and the elastic members 5 and 5 is not particularly limited as long as it has elastic elasticity such as thread-like rubber, flat rubber, ribbon-like elastic body, and water-absorbing shrinkable fiber.

The absorbent body 4 is preferably formed in the shape of an hourglass with a narrowed crotch portion, which is easy to apply to the crotch and is excellent in fit. As the absorbent body 4, the main material is defibrated pulp,
It is preferable to use a high-molecular water-absorbing polymer in combination, and in addition, it is preferable to use a mixture of cellulose fibers, a thermoplastic resin, and a high-molecular water-absorbing polymer which is heat-treated. The high-molecular water-absorbing polymer may be present in any of the upper layer, the middle layer, and the lower layer, and may be mixed with the pulp. The high molecular weight water-absorbing polymer preferably has a property of absorbing and retaining a liquid 20 times or more its own weight and has a property of gelling. Examples of such a high molecular weight water-absorbing polymer include starch-acrylic acid. (Salt) graft copolymer, saponification product of starch-acrylonitrile copolymer, crosslinked product of sodium carboxymethyl cellulose, acrylic acid (salt) polymer and the like are preferable. As the surface sheet 2,
It is preferable that the liquid-permeable sheet that allows excrement to pass through the absorbent body 4 has a feeling close to that of underwear. Examples of such a liquid-permeable sheet include woven fabrics, non-woven fabrics, and porous materials that have recently begun to come into the limelight. Films and the like are preferable. Also,
Water repellent treatment is carried out by applying a hydrophobic compound such as a silicone oil or paraffin wax to the peripheral portion of the topsheet 2, or by applying a hydrophilic compound such as an alkyl phosphate ester and washing with warm water at the peripheral edge. It is preferable that the treatment is performed to prevent leakage of urine or the like at the peripheral portion due to bleeding.

The back sheet 3 is made by adding a filler to a thermoplastic resin and stretching it, and is a vapor-permeable, liquid-impermeable sheet having vapor permeability, or a sheet having a feel similar to underwear, for example, a composite of a film and a nonwoven fabric. Material or the like is used.

The base material of the fastening tapes 7, 7 is generally paper, cellophane, acetate film, cloth,
A material such as biaxially oriented polypropylene, polyethylene, polyethylene terephthalate, or a non-woven fabric is used, and an adhesive is used in combination with the base material. Adhesives basically consist of base polymer, tackifier, and softener, and are classified into rubber type, EVA type, olefin type, and acrylic type depending on the difference of base polymer, and generally rubber type adhesive for disposable diapers. Agents are used. The landing tapes 8 and 8 are the same as the fastening tapes. Generally, biaxially oriented polypropylene as the base material and a rubber-based hot melt agent as the adhesive are suitable. It should be noted that the embodiments of the fastening tape and the landing tape are not particularly limited to these configurations as long as they serve as a fastening system. For example, the fastening system may be a male and female Velcro fastener, or the landing tape may not be needed depending on the choice of fastener tape adhesive and backsheet substrate.

Next, FIG. 3 shows a perspective view of the disposable diaper 101 as seen from the top sheet 2 side according to the second embodiment of the present invention, and FIG. 4 shows all the disposable diapers 101 as seen from the top sheet 2 side. Shows a plan view with stretched elastic elements,
FIG. 5 shows a plan view of the disposable diaper 101 as seen from the back sheet 3 side. As shown in FIG. 3, the disposable diaper 101 of the present embodiment has a boat shape in a natural state where no stress is applied. Disposable diaper 101
Applies the fastening tapes 7 and 7 to the wearer's dorsal side and the landing tapes 8 and 8 to the wearer's abdominal side,
Fastening tape 7,7 landing tape 8,8
Applied to the wearer by adhesively fixing to.

4 and 5 are plan views of a disposable diaper 101 which is a second embodiment of the present invention. With respect to the configuration of the disposable diaper 101, the members substantially similar to those of the disposable diaper 1 according to the first embodiment of the present invention are denoted by the same symbols as those in FIG. 1, and the description thereof will be omitted.
The absorbent body 4 of the disposable diaper 101 according to the second embodiment of the present invention has notches 14A and 14B formed in the widthwise central portions of both longitudinal ends thereof. This notch 14A,
14B plays the same role as the low basis weight portions 13A and 13B described above, and prevents the waist band from warping,
Improves leak prevention performance.

[0020]

According to the disposable diaper of the present invention, the waist band is prevented from warping, the absorber can be brought into close contact with the wearer, and the leakage preventing performance of the disposable diaper is improved.

[Brief description of drawings]

FIG. 1A is a plan view of a disposable diaper, which is an embodiment of the present invention, in a stretched state, viewed from the surface sheet side, and FIG. 1B is a disposable diaper shown in FIG. X
-X line sectional view, and (c) is a YY line sectional view of the disposable diaper shown by (a).

FIG. 2 is a plan view of the disposable diaper, which is an embodiment of the present invention, in an extended state, as viewed from the back sheet side.

FIG. 3 is a perspective view of a disposable diaper according to another embodiment of the present invention in a natural state.

FIG. 4 is a plan view of the disposable diaper shown in FIG. 3 when viewed from the top sheet side in an expanded state.

FIG. 5 is a plan view of the disposable diaper shown in FIG. 3 as viewed from the back sheet side in an expanded state.

[Explanation of symbols]

 1,101 Disposable diaper 2 Topsheet 3 Backsheet 4 Absorber 6 Waistband 6A, 6B Elastic member for waistband 13A, 13B Low basis weight portion 14A, 14B Notch portion

Claims (6)

[Claims] 1. A liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber positioned between the two sheets, wherein a pair of tape fasteners are arranged at both edges on the back side. , A landing zone for attaching the tape fastener is arranged on the back sheet on the abdomen side, leg gathers are arranged so as to be able to expand and contract around both legs, and a waist band is formed on at least one of the abdomen side and the back side. In the disposable diaper arranged to be stretchable around the waist, the portion of the absorber in the stretchable portion of the waistband has a lower rigidity than other portions of the absorber. Disposable diaper. 2. The disposable diaper according to claim 1, wherein the rigidity of the low-rigidity portion of the absorbent body on which the waist band is arranged is 10 g · cm or less. 3. The disposable diaper according to claim 1, wherein the portion of the absorbent body where the landing zone overlaps has a higher rigidity than other portions of the absorbent body. 4. A liquid-permeable top sheet, a liquid-impermeable back sheet, and an absorber positioned between these sheets, and a pair of tape fasteners are arranged at both edges on the back side. , A landing zone for attaching the tape fastener is arranged on the back sheet on the abdomen side, leg gathers are arranged so as to be able to expand and contract around both legs, and a waist band is formed on at least one of the abdomen side and the back side. In the disposable diaper arranged to be stretchable around the waist, the waist band is attached to an upper portion of the absorbent body on the back side or the abdominal side, and the absorbent body is arranged with the waist band. Disposable diaper characterized by notching the part that requires expansion and contraction. 5. The disposable diaper according to claim 1, wherein the absorbent body has a substantially hourglass shape in which a crotch portion when worn is constricted. 6. The stretching stress line of the leg gathers arranged so as to be capable of stretching around the both legs is fixed so as to intersect with the stretching stress line of the waistband for the waistline, and both of them cooperate with each other when worn. The disposable diaper according to claim 1, wherein the disposable diaper operates by working.